CN109776707B - Method for producing rare earth isoprene rubber - Google Patents
Method for producing rare earth isoprene rubber Download PDFInfo
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Abstract
The invention relates to the field of polymer production, and discloses a method for producing rare earth isoprene rubber, which comprises the following steps: under the condition of solution polymerization, introducing an isoprene monomer, a rare earth catalyst and a solvent into a polymerization reaction unit for polymerization reaction, circulating part of rare earth isoprene rubber liquid solution obtained at an outlet of the polymerization reaction unit back to an inlet of the polymerization reaction unit, introducing the rest of rare earth isoprene rubber liquid solution serving as a crude product into a subsequent processing unit, wherein the weight of the rare earth isoprene rubber liquid solution circulated back to the inlet of the polymerization reaction unit is 5-25 wt% based on the total weight of all the rare earth isoprene rubber liquid solutions obtained at the outlet of the polymerization reaction unit. The method can reduce the addition amount of the solvent in the polymerization reaction unit, further reduce the steam consumption for recovering the solvent and achieve better energy-saving effect.
Description
Technical Field
The invention relates to the field of polymer production, in particular to a method for producing rare earth isoprene rubber.
Background
The rare earth isoprene rubber is one of synthetic rubbers, and is a polymer generated by polymerization reaction of isoprene monomers under the action of a catalyst.
Since the physical and mechanical properties of rare earth isoprene rubber are similar to those of Natural Rubber (NR), rare earth isoprene rubber is also called "synthetic natural rubber". Specifically, rare earth isoprene rubber has excellent elasticity, sealing property, creep resistance, abrasion resistance, heat resistance and tear resistance, and also has tensile strength and elongation close to those of natural rubber, and thus can be used as an alternative to natural rubber in some cases, and can also be used in combination with natural rubber or other synthetic rubbers.
Generally, in the production of synthetic rubbers, the polymerization of monomers with catalysts is carried out mainly by: bulk polymerization, suspension polymerization, emulsion polymerization, solution polymerization, slurry polymerization, gas phase polymerization, and the like.
With the advent of Z-N catalysts and the development of ionic catalysts since the 50's of the 20 th century, the synthetic rubber industry employing solution polymerization has not only expanded increasingly but has become the dominant polymerization process. In the solution polymerization method, a solvent needs to be introduced into a polymerization system, so that the viscosity of the system is lower than that of bulk polymerization, mixing and heat dissipation are easier, production operation and temperature are easy to control, polymerization heat can be removed by utilizing the heat absorption of the solvent to avoid sudden polymerization, and the structure of a polymerization reactor is further simplified.
The Russian Kauchuk company adopts a solution polymerization method to synthesize the rare earth isoprene rubber, and successfully produces the rare earth isoprene rubber product with cis-1, 4-configuration content as high as 96 weight percent in a three-kettle series continuously-operated industrial device.
When the rare earth isoprene rubber is prepared by adopting a solution polymerization method, in order to obtain a pure rare earth isoprene rubber polymer, enough energy needs to be provided to separate a solvent added during polymerization from a rare earth isoprene rubber liquid, and the solvent is recycled. The more solvent is added during polymerization, the lower the concentration of the polymer in the obtained rare earth isoprene rubber liquid, and the larger the amount of solvent which needs to be separated and recovered subsequently, so the more energy needs to be consumed.
In the prior art, after the rare earth isoprene rubber liquid is obtained by adopting a solution polymerization method, a solvent is stripped from the rare earth isoprene rubber liquid by adopting a condensation process. In the condensation unit, the principle of steam distillation is adopted, the glue solution is sprayed into hot water which is used as a heat transfer medium and a conveying medium, and about 95 weight percent of solvent is stripped out by means of steam, so that the purpose of separating the rare earth isoprene rubber polymer from the solvent is achieved. The solvent stripped by the steam enters a solvent recovery unit to finish the refining of the solvent; the refined solvent is recycled to the polymerization section for reuse. In the solvent recovery unit, several distillation columns are usually used to purify the solvent, and the bottom of each distillation column is provided with a reboiler, and steam needs to be introduced into the reboiler to provide sufficient heat for the separation of the components.
At present, the weight concentration of the rare earth isoprene rubber glue solution obtained by a polymerization unit in the prior art is in a range of 13-16%, namely the solvent consumption of each ton of rare earth isoprene rubber is more than 5 tons, so that the total steam consumption in a condensation unit and a solvent recovery unit is large, and the energy consumption in the production cost is high. Therefore, the polymerization process needs to be optimized deeply to reduce the amount of solvent added during the polymerization process as much as possible, and further reduce the amount of steam consumed by the subsequent solvent stripping and recovery refining.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide a novel energy-saving method for producing rare earth isoprene rubber on the premise of keeping and even improving the concentration of the produced rare earth isoprene rubber liquid.
The inventor of the invention finds that a large amount of polymerization heat is generated during the polymerization reaction of isoprene, the viscosity of the isoprene rubber solution obtained by polymerization is high, and if the isoprene rubber is prepared only by adopting a temperature control mode of jacket heat removal, the heat transfer of a reactor is quite difficult. For improvement, polymerization can generally be carried out using a polymerization technique combining low temperature feeding (even large solvent feeding) with jacket heat removal. However, when the polymerization is carried out by a polymerization technique combining low-temperature feeding and jacket heat removal, 5 tons or more of solvent is required to be charged into the polymerization reactor for absorbing a large amount of polymerization heat per one ton of dry rubber produced, and if the solvent is recovered, a large amount of energy is required. Moreover, when the method provided by the prior art is adopted to produce isoprene rubber, the concentration of the obtained isoprene rubber glue solution is lower.
In order to overcome the above-mentioned drawbacks of the prior art, the inventors of the present invention have provided, through inventive research, the following method for producing a rare earth isoprene rubber, the method comprising: under the condition of solution polymerization, introducing an isoprene monomer, a rare earth catalyst and a solvent into a polymerization reaction unit for polymerization reaction, circulating part of rare earth isoprene rubber liquid solution obtained at an outlet of the polymerization reaction unit back to an inlet of the polymerization reaction unit, introducing the rest of rare earth isoprene rubber liquid solution serving as a crude product into a subsequent processing unit, wherein the weight of the rare earth isoprene rubber liquid solution circulated back to the inlet of the polymerization reaction unit is 5-25 wt% based on the total weight of all the rare earth isoprene rubber liquid solutions obtained at the outlet of the polymerization reaction unit.
The invention provides a novel method for producing rare earth isoprene rubber aiming at the problem of high energy consumption of the rare earth isoprene rubber production process in the prior art, and the method can reduce the addition amount of the solvent in a polymerization reaction unit by returning the polymerized rare earth isoprene rubber liquid with a specific weight ratio to the inlet of the polymerization reaction unit to replace part of the solvent for removing polymerization heat, thereby reducing the steam consumption for recovering the solvent and achieving a better energy-saving effect.
Drawings
FIG. 1 is a schematic view of a process flow for producing rare earth isoprene rubber according to a preferred embodiment of the present invention.
Description of the reference numerals
1. Isoprene monomer 2, solvent
3. Part of rare earth isoprene rubber cement liquid recycled to the inlet of the polymerization reactor
4. The rare earth isoprene rubber liquid as the residual part of the crude product introduced into the subsequent processing unit
A. A first reactor B and a second reactor
C. Third reactor
Detailed Description
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
As described above, the present invention provides a method for producing a rare earth isoprene rubber, comprising: under the condition of solution polymerization, introducing an isoprene monomer, a rare earth catalyst and a solvent into a polymerization reaction unit for polymerization reaction, circulating part of rare earth isoprene rubber liquid solution obtained at an outlet of the polymerization reaction unit back to an inlet of the polymerization reaction unit, introducing the rest of rare earth isoprene rubber liquid solution serving as a crude product into a subsequent processing unit, wherein the weight of the rare earth isoprene rubber liquid solution circulated back to the inlet of the polymerization reaction unit is 5-25 wt% based on the total weight of all the rare earth isoprene rubber liquid solutions obtained at the outlet of the polymerization reaction unit.
In the method for producing the rare earth isoprene rubber, the solution polymerization reaction can be carried out in a manner of removing heat by a jacket to control the reaction temperature, and can also be carried out in a manner of adiabatic polymerization, and preferably, the solution polymerization reaction is carried out in an adiabatic polymerization manner.
The polymerization reaction unit may be a conventional tank polymerization reactor or other type of polymerization reactor commonly used in the art, and preferably, the polymerization reaction unit is a tank polymerization reactor. The polymerization reaction unit of the present invention may be a reactor, i.e., a kettle reactor; or at least two reactors connected in series, namely a multi-kettle reactor; preferably, the polymerization reaction unit of the present invention is a two-pot reactor formed by two reactors connected in series, or a three-pot reactor formed by three reactors connected in series. The volume of the polymerization reactor is not particularly limited and may be various sizes conventionally used in the art, and preferably, when the polymerization reaction unit is formed of at least two reactors connected in series, the volumes of the respective reactors forming the polymerization reaction unit are equal.
The outlet of the polymerization unit is the outlet of the entire polymerization unit, that is, the outlet of the last reactor if there are two or more reactors.
The inlet of the polymerization reaction unit refers to the inlet of the whole polymerization reaction unit, that is, if there are two or more reactors, the inlet of the polymerization reaction unit refers to the inlet of the first reactor.
The part of the rare earth isoprene rubber glue solution is a part of the whole rare earth isoprene rubber glue solution obtained from the outlet of the polymerization reaction unit.
The residual rare earth isoprene rubber solution refers to the residual rare earth isoprene rubber solution obtained by subtracting the part of the rare earth isoprene rubber solution recycled to the inlet of the polymerization reaction unit from the whole rare earth isoprene rubber solution obtained at the outlet of the polymerization reaction unit.
The specific process of the solution polymerization is well known to those skilled in the art, and the present invention will not be described in detail herein.
Preferably, the total weight of all rare earth isoprene rubber liquid obtained at the outlet of the polymerization reaction unit is 10-20 wt% of the rare earth isoprene rubber liquid circulated back to the inlet of the polymerization reaction unit. The inventor of the invention finds that the method for producing the rare earth isoprene rubber is easy to operate and has more obvious energy-saving effect when the total weight of all the rare earth isoprene rubber liquid obtained at the outlet of the polymerization reaction unit is taken as a reference and the weight of the rare earth isoprene rubber liquid circulated to the inlet of the polymerization reaction unit is within the range of 10-20 wt%.
Preferably, the temperature of the part of the rare earth isoprene rubber glue solution which is circulated back to the inlet of the polymerization reaction unit is 0-20 ℃.
More preferably, the temperature of the rare earth isoprene rubber glue solution which is circulated back to the inlet of the polymerization reaction unit is 5-15 ℃. The inventor finds that when the temperature of the rare earth isoprene rubber liquid circulating back to the inlet of the polymerization reaction unit is controlled within the range of 5-15 ℃, the method for producing the rare earth isoprene rubber is easy to operate, has a more obvious energy-saving effect, does not reduce the operation load of isoprene monomers, and ensures the capacity of a rare earth isoprene rubber device.
In order to ensure that the temperature of the rare earth isoprene rubber cement solution circulated back to the inlet of the polymerization reaction unit is within the aforementioned range, a person skilled in the art may use a method commonly used in the art to cool the part of the rare earth isoprene rubber cement solution circulated back to the inlet of the polymerization reaction unit, for example, may use a method of heat exchange, and specifically, may use a refrigerant to exchange heat with the part of the rare earth isoprene rubber cement solution circulated back to the inlet of the polymerization reaction unit.
Preferably, the weight ratio of the isoprene monomer to the solvent is 1: (2-4.5). More preferably, the isoprene monomer and the solvent are used in a weight ratio of 1: (2.3-4). By adopting the method for circulating part of the rare earth isoprene rubber glue solution to the inlet of the polymerization reaction unit, the usage amount of the solvent is obviously lower than that of the method in the prior art, so that the production cost is saved; moreover, the amount of the solvent used is reduced, and the amount of steam consumed by recovering the solvent can be reduced, so that the production energy consumption is saved.
Preferably, the weight ratio of the rare earth catalyst to the isoprene monomer is (0.01-0.5): 1; more preferably, the weight ratio of the rare earth catalyst to the isoprene monomer is (0.02-0.35): 1.
preferably, the rare earth catalyst is selected from at least one of neodymium-based catalysts; more preferably, the neodymium-based catalyst is selected from at least one of neodymium naphthenate, neodymium octoate, neodymium isooctanoate, neodymium nonanoate, neodymium neodecanoate, neodymium decanoate, and neodymium phosphonate; particularly preferably, the neodymium-based catalyst is selected from at least one of neodymium naphthenate, neodymium neodecanoate, and neodymium phosphonate. For example, the rare earth catalyst may be a rare earth catalyst disclosed in the prior art such as CN103450373A, CN105330763A, CN105330773A, and the like.
Preferably, the solution polymerization conditions include: the solution polymerization reaction conditions include: the polymerization reaction temperature is 20-70 ℃, and more preferably 35-55 ℃; the polymerization time is 60 to 180 minutes, and more preferably 80 to 150 minutes. The inventor of the invention finds that when the condition of the solution polymerization reaction is controlled within the parameter range, the solvent usage amount of the process method for producing the rare earth isoprene rubber can be obviously reduced on the premise of ensuring that a rare earth isoprene rubber product with the quality equivalent to that of the prior art is obtained by matching with the process of circulating part of the rare earth isoprene rubber liquid to the inlet of the polymerization reaction unit. Further, when the polymerization reaction unit is a polymerization reactor formed by connecting at least two reactors in series, the solution polymerization reaction conditions in the respective reactors may be the same or different, and preferably the solution polymerization reaction conditions in the respective reactors are different.
Preferably, the temperature of the isoprene monomer, the rare earth catalyst and the solvent is not higher than 0 ℃ before entering the polymerization reaction unit for polymerization reaction; more preferably the temperature is from-20 ℃ to-2.5 ℃.
The method for producing the rare earth isoprene rubber can adopt a batch process operation mode and also can adopt a continuous process operation mode, and specifically, the batch process operation method is that the isoprene monomer, the solvent and the rare earth catalyst are put into a polymerization reaction unit at one time step by step in the production process, and the polymerization reaction unit does not have feeding and discharging operations in the reaction process. And when the reaction is finished, discharging a part of glue solution obtained in the polymerization reaction unit out of the polymerization reaction unit, and taking the rest glue solution as circulating glue solution to be left in the polymerization reaction unit to replace the solvent so as to reduce the addition of the solvent in the polymerization reaction of the next batch, thereby realizing energy conservation and consumption reduction.
In addition, the continuous process operation method is to continuously add the isoprene monomer, the solvent and the rare earth catalyst in the production process and continuously produce the rare earth isoprene rubber glue solution at the same time, so that the total amount of materials in the polymerization reaction unit is kept relatively stable, and the method for preferably producing the rare earth isoprene rubber adopts a continuous process operation mode, and the average residence time of the isoprene monomer in the polymerization reaction unit is 20-50 min.
Preferably, the polymerization reaction unit comprises at least three polymerization reactors connected in series in sequence, and part of the rare earth isoprene rubber cement solution obtained at the outlet of the last polymerization reactor is recycled to the inlet of the first polymerization reactor. More preferably, the polymerization reaction unit comprises three polymerization reactors connected in series in sequence.
Preferably, the solvent is selected from at least one of n-hexane, cyclohexane, methylcyclohexane, n-heptane, and n-octane; more preferably, the solvent is selected from at least one of n-hexane, cyclohexane and n-heptane.
According to a preferred embodiment, the method for producing rare earth isoprene rubber of the invention is carried out according to the process flow diagram shown in fig. 1, specifically, a polymerization reaction unit is composed of three reactors connected in series in sequence, isoprene monomer 1, solvent 2 and rare earth catalyst (not shown) sequentially pass through a first reactor a, a second reactor B and a third reactor C, and a part of rare earth isoprene rubber glue solution 3 recycled to the inlet of the polymerization reaction unit obtained from the outlet of the third reactor C is returned to the inlet of the first reactor a, and the rest of rare earth isoprene rubber glue solution introduced into a subsequent processing unit as a crude product is introduced into the subsequent processing unit for desolventizing treatment.
By adopting the method for producing the rare earth isoprene rubber, the concentration of the rare earth isoprene rubber liquid obtained from the outlet of the polymerization reactor can reach 18-22 wt%. Moreover, the method of the invention obviously reduces the addition amount of the solvent, reduces the consumption of the solvent, further reduces the consumption of steam for recovering the solvent, and has certain energy-saving effect.
The solvent amount required to be added in each ton of dry glue produced by adopting the method can be reduced to 65-85 wt% in the prior art.
The present invention will be described in detail below by way of examples.
Unless otherwise specified, various raw materials used below are commercially available.
Unless otherwise specified, various raw materials used below are commercially available. In all examples and comparative examples, the starting materials used were of the same specification, and the solvent was n-hexane. The catalysts are all rare earth catalysts used in example 1 of CN 103450373A.
In order to more clearly illustrate the method of producing rare earth isoprene rubber of the present invention, the following examples and comparative examples were all subjected to adiabatic polymerization using the operating temperature and outlet conversion shown in Table 1.
TABLE 1
| Operating temperature/. degree.C | Outlet conversion/weight% | |
| First reactor | 35 | 58 |
| Second reactor | 42 | 80 |
| Third reactor | 55 | 95 |
Examples 1 to 6 are intended to illustrate the process for producing a rare earth isoprene rubber of the present invention.
Example 1
In this example, solution polymerization was carried out using polymerization reactors in which three reactors shown in FIG. 1 were connected in series, each having a volume of 120L, and a continuous process was employed.
In the first reactor of this example, the total feed rate of the materials (including the circulating glue solution, the same below) was 112.5kg/h, wherein the feed rate of the isoprene monomer was 21.5kg/h, the feed rate of the solvent was 79.4kg/h, the feed rate of the catalyst was 5.6kg/h, and the feed temperatures of the three materials after cooling by the ethylene glycol refrigerator were-5 ℃, so as to control the operating temperatures and the outlet conversion rates of the three reactors as shown in table 1. And the amount of the rare earth isoprene rubber glue solution circulated back to the inlet of the first reactor is 6kg/h, and before entering the inlet of the first reactor, the temperature of the circulating glue solution from the third reactor is cooled to 15 ℃ by low-temperature water. The average residence time of the materials in each reactor was 40min, and after the polymerization in the adiabatic solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were measured to be 11.5 wt%, 15.6 wt% and 18.2 wt%, respectively, and the amount of the solvent finally required in the polymerization process was 4.5t/t dry glue. The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
Example 2
This example was carried out using the same polymerization reactor as in example 1.
In the first reactor of this example, the total feed rate of the materials was 112.5kg/h, wherein the feed rate of isoprene monomer was 21.5kg/h, the feed rate of solvent was 64.4kg/h, the feed rate of catalyst was 5.6kg/h, and the feed temperatures of the three materials after cooling by the ethylene glycol chiller were all-5 ℃, so as to control the operating temperatures and the outlet conversion rates of the three reactors as shown in table 1. And the amount of the rare earth isoprene rubber glue solution circulated back to the inlet of the first reactor is 21kg/h, and before entering the inlet of the first reactor, the temperature of the circulating glue solution from the third reactor is cooled to 5 ℃ by low-temperature water. The average residence time of the materials in each reactor was 40min, and after the polymerization in the adiabatic solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were measured to be 12.7 wt%, 16.6 wt% and 19.5 wt%, respectively, and the amount of the solvent finally required in the polymerization process was 4.1t/t dry glue. The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
Example 3
This example was carried out using the same polymerization reactor as in example 1.
In the first reactor of this example, the total feed rate of the materials was 130kg/h, wherein the feed rate of isoprene monomer was 26.5kg/h, the feed rate of solvent was 83.6kg/h, the feed rate of catalyst was 6.9kg/h, and the feed temperatures of the three materials after cooling by the ethylene glycol refrigerator were all-10 ℃, so as to control the operating temperatures and the outlet conversion rates of the three reactors as shown in table 1. And the amount of the rare earth isoprene rubber glue solution circulated back to the inlet of the first reactor is 13kg/h, and before entering the inlet of the first reactor, the temperature of the circulating glue solution from the third reactor is cooled to 16 ℃ by low-temperature water. The average residence time of the materials in each reactor was 35min, and after the polymerization in the adiabatic solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were measured to be 12.2 wt%, 16.7 wt% and 19.4 wt%, respectively, and the amount of the solvent finally required in the polymerization process was 4.1t/t dry glue. The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
Example 4
This example was carried out using the same polymerization reactor as in example 1.
In the first reactor of this example, the total feed rate of the materials was 130kg/h, wherein the feed rate of isoprene monomer was 26.5kg/h, the feed rate of solvent was 70.6kg/h, the feed rate of catalyst was 6.9kg/h, and the feed temperatures of the three materials after cooling by the ethylene glycol refrigerator were all-10 ℃, so as to control the operating temperatures and the outlet conversion rates of the three reactors as shown in table 1. And the amount of the rare earth isoprene rubber glue solution circulated back to the inlet of the first reactor is 26kg/h, and before entering the inlet of the first reactor, the temperature of the circulating glue solution from the third reactor is cooled to 3 ℃ by low-temperature water. The average residence time of the materials in each reactor was 35min, and after the polymerization in the adiabatic solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were measured to be 13.8 wt%, 18.3 wt% and 21 wt%, respectively, and the final solvent amount required in the polymerization process was 3.8t/t dry glue. The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
Example 5
This example was carried out using the same polymerization reactor as in example 1.
In the first reactor of this example, the total feed rate of the materials was 150kg/h, wherein the feed rate of isoprene monomer was 33kg/h, the feed rate of solvent was 93.5kg/h, the feed rate of catalyst was 7.5kg/h, and the feed temperatures of the three materials after cooling by the ethylene glycol refrigerator were all-15 ℃, so as to control the operating temperatures and the outlet conversion rates of the three reactors as shown in table 1. And the amount of the rare earth isoprene rubber glue solution circulated back to the inlet of the first reactor is 15kg/h, and before entering the inlet of the first reactor, the temperature of the circulating glue solution from the third reactor is cooled to 16.5 ℃ by low-temperature water. The average residence time of the materials in each reactor is 30min, and after the polymerization of the heat insulation solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor are respectively 13.2 wt%, 18 wt% and 21 wt%, and the finally required solvent amount in the polymerization process is 3.8t/t dry glue. The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
Example 6
This example was carried out using the same polymerization reactor as in example 1.
In the first reactor of this example, the total feed rate of the materials was 150kg/h, wherein the feed rate of isoprene monomer was 33kg/h, the feed rate of solvent was 78.5kg/h, the feed rate of catalyst was 7.5kg/h, and the feed temperatures of the three materials after cooling by the ethylene glycol refrigerator were all-15 ℃, so as to control the operating temperatures and the outlet conversion rates of the three reactors as shown in table 1. And the amount of the rare earth isoprene rubber glue solution circulated back to the inlet of the first reactor is 30kg/h, and before entering the inlet of the first reactor, the temperature of the circulating glue solution from the third reactor is cooled to 2 ℃ by low-temperature water. The average residence time of the materials in each reactor was 30min, and after the polymerization in the adiabatic solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were 14.8 wt%, 19.5 wt% and 22 wt%, respectively, and the final solvent amount required in the polymerization process was 3.6t/t dry glue. The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
From the results of the above examples 1-6, it can be seen that the glue solution obtained by the method of the present invention has a high concentration, and the amount of the solvent used in the polymerization process is low, even significantly lower than the solvent usage level of the prior art, thus demonstrating that the method of the present invention has a significant energy saving effect.
Comparative example 1
This comparative example was conducted in a similar manner to example 1, except that no circulating glue was provided in this comparative example, that is, all of the rare earth isoprene glue obtained from the outlet of the third reactor in this comparative example was introduced as a crude product into the subsequent processing unit. The total material feeding amount is 112.5kg/h, wherein the feeding amount of the isoprene monomer is 21.5kg/h, the feeding amount of the solvent is 85.4kg/h, the feeding amount of the catalyst is 5.6kg/h, the feeding temperatures of the three materials after being cooled by an ethylene glycol refrigerating unit are all-5 ℃, and the average residence time of the materials in each reactor is 40 min.
Then, after the polymerization in the adiabatic solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were measured to be 8.9 wt%, 13.5 wt% and 15.9 wt%, respectively, and the amount of the solvent finally required in the polymerization process was 5.3t/t dry glue. The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
Comparative example 2
This comparative example was carried out in a similar manner to comparative example 1, except that the total feed rate of the materials in this comparative example was 130kg/h, wherein the feed rate of the isoprene monomer was 26.5kg/h, the feed rate of the solvent was 96.6kg/h, the feed rate of the catalyst was 6.9kg/h, and the feed temperatures of the three streams of materials after cooling by the ethylene glycol refrigerator group were-10 ℃, and the average residence time of the materials in each reactor was 35 min.
Then, after the polymerization in the adiabatic solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were measured to be 10 wt%, 14.6 wt% and 16.7 wt%, respectively, and the amount of the solvent finally required in the polymerization process was 5t/t dry glue. The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
Comparative example 3
This comparative example was carried out in a similar manner to comparative example 1, except that the total feed rate of the materials in this comparative example was 150kg/h, the feed rate of the isoprene monomer was 33kg/h, the feed rate of the solvent was 109.5kg/h, the feed rate of the catalyst was 7.5kg/h, and the feed temperatures of the three streams of materials after cooling by the ethylene glycol refrigerator group were-15 ℃ and the average residence time of the materials in the respective reactors was 30 min.
Then, after the polymerization in the adiabatic solution, the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were measured to be 11.2 wt%, 15.8 wt% and 17.6 wt%, respectively, and the amount of the solvent finally required in the polymerization process was 4.7t/t dry glue.
The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
Comparative example 4
This comparative example was carried out in a similar manner to example 1, except that:
in the comparative example, the amount of the rare earth isoprene rubber cement solution circulated back to the inlet of the first reactor was 40 kg/h.
Specifically, in this example, the total material feeding amount is 112.5kg/h, wherein the feeding amount of isoprene monomer is 15kg/h, the feeding amount of solvent is 93.6kg/h, the feeding amount of catalyst is 3.9kg/h, and the feeding temperatures of the three materials after being cooled by the ethylene glycol refrigerator set are all-5 ℃.
The rest is the same as in example 1.
As a result: the concentrations of the glue solutions at the outlets of the first reactor, the second reactor and the third reactor were measured to be 11.6 wt%, 14.5 wt% and 16.2 wt%, respectively, and the amount of solvent required in the polymerization process was 5.2t/t dry glue.
The results of mass analysis of the obtained rare earth isoprene rubber products are shown in the following table 2.
TABLE 2
The results of the comparative examples and the comparative examples show that when the method is used for producing the rare earth isoprene rubber, the solvent consumption in the polymerization process can be obviously reduced, the solvent consumption per ton of dry rubber is reduced, the steam consumption for solvent recovery is further reduced, and a better energy-saving effect is achieved. Moreover, the quality of the rare earth isoprene rubber product obtained by the method of the embodiment of the invention is equivalent to or even better than that of the rare earth isoprene rubber product obtained by the method of the comparative example.
The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.
Claims (19)
1. A method for producing rare earth isoprene rubber, comprising: under the condition of solution polymerization, introducing an isoprene monomer, a rare earth catalyst and a solvent into a polymerization reaction unit for polymerization reaction, circulating part of rare earth isoprene rubber glue solution obtained at an outlet of the polymerization reaction unit back to an inlet of the polymerization reaction unit, introducing the rest of rare earth isoprene rubber glue solution serving as a crude product into a subsequent processing unit, wherein the weight of the rare earth isoprene rubber glue solution circulated back to the inlet of the polymerization reaction unit is 5-25 wt% based on the total weight of all the rare earth isoprene rubber glue solution obtained at the outlet of the polymerization reaction unit;
the weight ratio of the isoprene monomer to the solvent is 1: (2-4.5).
2. The method according to claim 1, wherein the temperature of the part of the rare earth isoprene rubber cement which is circulated back to the inlet of the polymerization reaction unit is 0-20 ℃.
3. The method according to claim 1, wherein the temperature of the part of the rare earth isoprene rubber cement circulated back to the inlet of the polymerization reaction unit is 5-15 ℃.
4. The method according to any one of claims 1 to 3, wherein the amount of the rare earth isoprene rubber cement circulated back to the inlet of the polymerization reaction unit is 10 to 20 wt% based on the total weight of all the rare earth isoprene rubber cement obtained at the outlet of the polymerization reaction unit.
5. The method of claim 1, wherein the isoprene monomer and the solvent are used in a weight ratio of 1: (2.3-4).
6. The method of claim 1, wherein the rare earth catalyst and the isoprene monomer are used in a weight ratio of (0.01-0.5): 1.
7. the method according to claim 1, wherein the weight ratio of the rare earth catalyst to the isoprene monomer is (0.02-0.35): 1.
8. the process according to claim 1 or 6, wherein the rare earth catalyst is selected from at least one of neodymium based catalysts.
9. The method of claim 8, wherein the neodymium is catalytic to at least one selected from neodymium naphthenate, neodymium octoate, neodymium isooctanoate, neodymium nonanoate, neodymium neodecanoate, neodymium decanoate, and neodymium phosphonate.
10. The method of claim 8, wherein the neodymium is catalytic to at least one selected from neodymium naphthenate, neodymium neodecanoate, and neodymium phosphonate.
11. The method of any of claims 1-3, wherein the solution polymerization reaction conditions comprise: the polymerization temperature is 20-70 ℃, and the polymerization time is 60-180 minutes.
12. The method of any of claims 1-3, wherein the solution polymerization reaction conditions comprise: the polymerization temperature is 35-55 ℃, and the polymerization time is 80-150 minutes.
13. The method of claim 1, wherein the temperature of the isoprene monomer, the rare earth catalyst, and the solvent is not higher than 0 ℃ before entering the polymerization reaction unit for polymerization.
14. The method of claim 1, wherein the temperature of the isoprene monomer, the rare earth catalyst, and the solvent is from-20 ℃ to-2.5 ℃ before entering the polymerization reaction unit for polymerization.
15. The method of claim 1, wherein the method is performed as a continuous process.
16. The method as claimed in claim 1 or 15, wherein the polymerization reaction unit comprises at least three polymerization reactors connected in series in sequence, and part of the rare earth isoprene rubber cement liquid obtained at the outlet of the last polymerization reactor is recycled to the inlet of the first polymerization reactor.
17. The process of claim 16, wherein the polymerization reaction unit comprises three polymerization reactors connected in series.
18. The method of claim 1, wherein the solvent is selected from at least one of n-hexane, cyclohexane, methylcyclohexane, n-heptane, and n-octane.
19. The method of claim 1, wherein the solvent is selected from at least one of n-hexane, cyclohexane, and n-heptane.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4146693A (en) * | 1977-12-02 | 1979-03-27 | The B. F. Goodrich Company | Process for preparation of cis-1,4 poly(isoprene) |
| CN101880346A (en) * | 2010-07-19 | 2010-11-10 | 曹斌豫 | Method for synthesizing high-content cis-1,4-polyisoprene |
| CN102532379A (en) * | 2010-12-09 | 2012-07-04 | 中国石油化工股份有限公司 | Polymerization method for preparing rare earth isoprene rubber |
| CN104725564A (en) * | 2013-12-24 | 2015-06-24 | 青岛伊科思新材料股份有限公司 | Polymerization method of isoprene and butadiene |
| RU2014108167A (en) * | 2014-03-03 | 2015-09-20 | Евгений Семёнович Подвальный | METHOD FOR PRODUCING ISOPRENE RUBBER |
| CN105085755A (en) * | 2014-04-22 | 2015-11-25 | 中国石油化工股份有限公司 | Polyisoprene preparation method |
| CN105732867A (en) * | 2014-12-11 | 2016-07-06 | 中国石油天然气股份有限公司 | Solution polymerization method for rare earth isoprene rubber |
| JP2017057298A (en) * | 2015-09-17 | 2017-03-23 | 日立造船株式会社 | Polyisoprene production process |
-
2017
- 2017-11-10 CN CN201711106929.2A patent/CN109776707B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4146693A (en) * | 1977-12-02 | 1979-03-27 | The B. F. Goodrich Company | Process for preparation of cis-1,4 poly(isoprene) |
| CN101880346A (en) * | 2010-07-19 | 2010-11-10 | 曹斌豫 | Method for synthesizing high-content cis-1,4-polyisoprene |
| CN102532379A (en) * | 2010-12-09 | 2012-07-04 | 中国石油化工股份有限公司 | Polymerization method for preparing rare earth isoprene rubber |
| CN104725564A (en) * | 2013-12-24 | 2015-06-24 | 青岛伊科思新材料股份有限公司 | Polymerization method of isoprene and butadiene |
| RU2014108167A (en) * | 2014-03-03 | 2015-09-20 | Евгений Семёнович Подвальный | METHOD FOR PRODUCING ISOPRENE RUBBER |
| CN105085755A (en) * | 2014-04-22 | 2015-11-25 | 中国石油化工股份有限公司 | Polyisoprene preparation method |
| CN105732867A (en) * | 2014-12-11 | 2016-07-06 | 中国石油天然气股份有限公司 | Solution polymerization method for rare earth isoprene rubber |
| JP2017057298A (en) * | 2015-09-17 | 2017-03-23 | 日立造船株式会社 | Polyisoprene production process |
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